ENDOGENOUS SWITCHING OF INSURANCE REGIME AND THE DEMAND FOR HEALTH CARE SERVICES AMONG THE INSURED AND UNINSURED

Öz

Bir kişinin sağlık sigortasının olması sadece sağlık hizmetlerine harcadığı parayı değil aynı zamanda sağlık hizmetlerine ulaşabilmesini de etkiler. Bu çalışma sigortalılar ile sigortalı olmayanlar arasındaki sağlık hizmetleri talebinin belirleyicilerini incelemek için sağlık hizmetleri talebini sigorta rejimleri ile tahmin etmektedir. Sigortanın içselliği ve bağımlı değişkenin pozitifliği ve kesikli değişken olmasından dolayı bu tür bir analiz geleneksel tahmin yöntemleri ile yapılamamaktadır. Bundan dolayı bu çalışmada 1993 Milli Sağlık Araştırma Anketi kullanılarak type-5 Tobit modeli olarak da bilinen içsel switching model kullanılmıştır. Sağlık statüleri arasında belli anlamlı ilişkiler görülmüştür. Örneğin, çalışan bireyler daha az ameliyat ve hastanede daha az gece yatma talebinde bulunmaktadırlar. Bazı anlamlı ilişkiler ise sadece bir sigorta türünde görünmektedir. Örneğin, sigortalılar arasında daha yüksek eğitimli bireylerin daha fazla uzman vizitesi talep ettikleri gözlemlenmiştir. Doktor hizmetleri talebinde ise sağlık statüsünün sigortalı olmayanlar arasında sigortalılara göre daha etkili olduğu gözlemlenmiştir. Hastane hizmetleri talebi açısından ise bu ilişkinin ters olduğu gözlemlenmiştir. Bu sonuçlar göstermektedir ki sigorta bağımsız değişkenler ile sağlık hizmetlerinden faydalanma arasındaki ilişkiye etkileyebilmektedir.

Anahtar Kelimeler

• Sigorta Rejimi, Sigortalı Ve Sigortasız, Sağlık Hizmetleri

ENDOGENOUS SWITCHING OF INSURANCE REGIME AND THE DEMAND FOR HEALTH CARE SERVICES AMONG THE INSURED AND UNINSURED

Öz

Whether one has health insurance not only determines one's out-of-pocket health care costs, but also one's access to health care. This paper estimates the demand for a portfolio of health care services by insurance regime to examine the determinants of health care demand among the insured and uninsured. Such an analysis would not be possible using traditional estimation methods given the endogeneity of insurance, the change of insurance regime and the discreteness and the non-negativity of the dependent variable. These aspects motivate the application of an endogenous switching model for count data, also known as a type-5 Tobit, using the 1993 National Health Interview Survey. Certain significant relationships hold across insurance status. For example, employed individuals demand fewer operations and nights in the hospital. Certain significant relationships only appear in one insurance state. For example, among the insured, the higher educated individuals demand more specialist visits. In the demand for physician services, health status is more influential among the uninsured than the insured. This relationship is reversed in the demand for hospital services, where health is less influential among the uninsured than the insured. These results suggest that insurance likely modifies the relationship between the independent variables and health care utilization by providing an access to an entirely different system of care.

Anahtar Kelimeler

• Sigorta Rejimi, Sigortalı Ve Sigortasız, Sağlık Hizmetleri

Kaynakça

1. Cameron, A. C., P. K. Trivedi, F. Milne and J. Piggott (1988) “A Microeconometric Model of the Demand for Health Care and Health Insurance in Australia,” Review of Economic Studies, 55, 85-106.
2. Coulson, N. E., J. V. Terza, C. A. Neslusan and B. C. Stuart (1995) “Estimating the MoralHazard Effect of Supplemental Medical Insurance in the Demand for Prescription Drugs by the Elderly,” American Economic Review, 85, 122-126.
3. Dowd B., R. Feldman, S. Cassou and M. Finch (1991) "Health Plan Choice and the Utilization of Health Care Services," Review of Economics and Statistics, 73, 85-93.
4. Gruber J. (2000) "Health Insurance and the Labor Market," in Handbook of Health Economics, Culyer A.J. and J.P. Newhouse (eds.), North-Holland: Amsterdam, 646-706.
5. Heckman J.J. (1979) "Sample Selection Bias as a Specification Error," Econometrica, 47, 153- 162.
6. Kenkel D.S. and J.V. Terza (2001) "The Effect of Physician Advice on Alcohol Consumption: Count Regression with an Endogenous Treatment Effect," Journal of Applied Econometrics, 16, 165-184.
7. Lee L.F. (1978) "Unionism and Wage Rates: A Simultaneous Equations Model with Qualitative and Limited Dependent Variables," International Economic Review, 19, 415-433.
8. Manning W.G., A. Leibowitz, G.A. Goldberg, W.H. Rogers and J.P. Newhouse (1984) "A Controlled Trial of the Effect of a Prepaid Group Practice on Use of Services," New England Journal of Medicine, 310, 1505-1510.

9. McGeary K.A. and M.T. French (2000) "Illicit Drug Use and Emergency Room Utilization," Health Services Research, 35, 153-169.
10. Mort E.A., J.N. Edwards, D.W. Emmons, K. Convery and D. Blumenthal (1996) "Physician Response to Patient Insurance Status in Ambulatory Care Clinical Decision-Making: Implications for Quality of Care," Medical Care, 34, 783-797.
11. National Center for Health Statistics (U.S.) 1993. National Health Interview Survey and Health Insurance Supplement. The Center: Hyattsville, MD.
12. Newhouse J.P. and the Insurance Experiment Group (1993) Free for All? Lessons From the RAND Health Insurance Experiment, Harvard University Press: Cambridge, MA.
13. Schellhorn M. (2001) "The Effect of Variable Health Insurance Deductibles on the Demand for Physician Visits," Health Economics, 10, 441-456.
14. Terza J.V. (1998) "Estimating Count Data Models with Endogenous Switching: Sample Selection and Endogenous Treatment Effects," Journal of Econometrics, 84, 129-154.
15. Vera-Hernandez A.M. (1999) “Duplicate Coverage and Demand for Health Care: The Case of Catalonia,” Health Economics, 8, 579-598.